ASTM F1390-02

Standard Test Method for Measuring Warp on Silicon Wafers by Automated Noncontact Scanning (Withdrawn 2003)

SCOPE
This standard was transferred to SEMI (www.semi.org) May 2003
1.1 This test method covers a noncontacting, nondestructive procedure to determine the warp of clean, dry semiconductor wafers.
1.2 The test method is applicable to wafers 50 mm or larger in diameter, and 100 m (0.004 in.) approximately and larger in thickness, independent of thickness variation and surface finish, and of gravitationally-induced wafer distortion.
1.3 This test method is not intended to measure the flatness of either exposed silicon surface. Warp is a measure of the distortion of the median surface of the wafer.
1.4 This test method measures warp of a wafer corrected for all mechanical forces applied during the test. Therefore, the procedure described gives the unconstrained value of warp. This test method includes a means of canceling gravity-induced deflection which could otherwise alter the shape of the wafer. The resulting parameter is described by Warp(2) in Shape Decision Tree in SEMI Specification M 1. (See Annex A1.)
Note 1— Test Method F 657 measures median surface warp using a three-point back-surface reference plane. The back-surface reference results in thickness variation being included in the recorded warp value. The use (in this test method) of a median surface reference plane eliminates this effect. The use (in this test method) of a least-squares fit reference plane reduces the variability introduced in three-point plane calculations by choice of reference point location. The use (in this test method) of special calibration or compensating techniques minimizes the effects of gravity-induced distortion of the wafer.
1.5 The values stated in SI units are to be regarded separately as the standard. The values given in parentheses are for information only.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Withdrawn
• Publication Date: 09-Dec-2002
• Withdrawal Date: 09-May-2003
• ICS: 29.045 - Semiconducting materials
• Technical Committee: F01 - Electronics

Relations

• Replaces: ASTM F1390-97 - Standard Test Method for Measuring Warp on Silicon Wafers by Automated Noncontact Scanning
• Effective Date: 10-Dec-2002

Standards Content (Sample)

NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: F 1390 – 02
Standard Test Method for
Measuring Warp on Silicon Wafers by Automated
1
Noncontact Scanning
This standard is issued under the fixed designation F 1390; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
1.1 This test method covers a noncontacting, nondestructive
procedure to determine the warp of clean, dry semiconductor
2. Referenced Documents
wafers.
2.1 ASTM Standards:
1.2 The test method is applicable to wafers 50 mm or larger
F 657 Test Method for Measuring Warp and Total Thickness
in diameter, and 100 μm (0.004 in.) approximately and larger in
Variation on Silicon Slices and Wafers by Noncontact
thickness, independent of thickness variation and surface
3
Scanning
finish, and of gravitationally-induced wafer distortion.
3
F 1241 Terminology of Silicon Technology
1.3 This test method is not intended to measure the flatness
2.2 SEMI Standard:
of either exposed silicon surface. Warp is a measure of the
M 1 Specifications for Polished Monocrystalline Silicon
distortion of the median surface of the wafer.
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Wafers
1.4 This test method measures warp of a wafer corrected for
all mechanical forces applied during the test. Therefore, the
3. Terminology
procedure described gives the unconstrained value of warp.
3.1 Definitions:
This test method includes a means of canceling gravity-
3.1.1 mechanical signature— of an instrument, that compo-
induced deflection which could otherwise alter the shape of the
2 nent of a measurement that is introduced by the instrument and
wafer. The resulting parameter is described by Warp(2) in
that is systematic, repeatable, and quantifiable.
Appendix X2 Shape Decision Tree in SEMI Specification M 1.
3.1.2 median surface—of a semiconductor wafer, the locus
(See Annex A1.)
of points equidistant from the front and back surfaces.
NOTE 1—Test Method F 657 measures median surface warp using a
3.1.3 quality area—that portion of a wafer within the
three-point back-surface reference plane. The back-surface reference
specified parameter is determined.
results in thickness variation being included in the recorded warp value.
3.1.4 reference plane— of a semiconductor wafer, a plane
The use (in this test method) of a median surface reference plane
from which deviations are measured.
eliminates this effect. The use (in this test method) of a least-squares fit
3.1.5 reference plane deviation (RPD)—the distance from a
reference plane reduces the variability introduced in three-point plane
calculations by choice of reference point location. The use (in this test point on a reference plane to the corresponding point on a
method) of special calibration or compensating techniques minimizes the
wafer surface. A dome-shaped wafer is considered to have
effects of gravity-induced distortion of the wafer.
positive RPD at its center; a bowl-shaped wafer is considered
1.5 The values stated in SI units are to be regarded sepa- to have negative RPD at its center.
3.1.6 thickness—of a semiconductor wafer, the distance
rately as the standard. The values given in parentheses are for
information only. through the wafer between corresponding points on the front
and back surfaces.
1.6 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the 3.1.7 wafer—of a semiconductor, the difference between
the maximum and minimum distances of the median surface of
responsibility of the user of this standard to establish appro-
a free, unclamped wafer from a reference plane.
3.1.7.1 Discussion—Although warp may be caused by un-
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This test method is under the jurisdiction of ASTM Committee F01 on
equal stresses on the two exposed surfaces of the wafer, it
Electronicsand is the direct responsibility of Subcommittee F01.06 on Silicon
cannot be determined from measurements on a single exposed
Materials and Process Control.
Current edition approved Dec. 10, 2002. Published March 2003. Originally
approved in 1992. Last previous edition approved in 1997 as F 1390 – 97.
2
Poduje, N., “Eliminating Gravitational Effect in Wafer Shape Measurements,”
3
NIST/ASTM/SEMI/SEMATECH Technology Conference, Dallas, TX; Technology Annual Book of ASTM Standards, Vol 10.05.
4
for Advanced Materials/Process Characterization, February 1, 1990. Available from SEMI, 805 East Middlefield Road, Mt. View, CA 94043.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
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